monitor/src/module/Module.cpp

   1 /**
   2         Aesalon, a tool to visualize a program's behaviour at run-time.
   3         Copyright (C) 2010, Aesalon Development Team.
   4
   5         Aesalon is distributed under the terms of the GNU GPLv3. For more
   6         licensing information, see the file LICENSE included with the distribution.
   7
   8         @file monitor/src/module/Module.cpp
   9
  10 */
  11
  12 #include <iostream>
  13
  14 #include <dlfcn.h>
  15
  16 #include "module/Module.h"
  17 #include "monitor/Coordinator.h"
  18 #include "common/Preprocessor.h"
  19 #include "common/StringTo.h"
  20
  21 namespace Monitor {
  22 namespace Module {
  23
  24 Module::Module(const std::string &moduleName) : m_moduleName(moduleName) {
  25         m_instance = NULL;
  26         loadPreprocessor();
  27         loadMarshaller();
  28 }
  29
  30 Module::~Module() {
  31         dlclose(m_marshallerHandle);
  32 }
  33
  34 void Module::loadMarshaller() {
  35         std::string path =
  36                 Coordinator::instance()->vault()->get(m_moduleName + ":root")
  37                 + Coordinator::instance()->vault()->get(m_moduleName + ":marshallerPath");
  38
  39         std::cout << path << std::endl;
  40
  41         m_marshallerHandle = dlopen(path.c_str(), RTLD_LOCAL | RTLD_NOW);
  42         if(m_marshallerHandle == NULL) {
  43                 return;
  44         }
  45
  46         Common::MarshallerInterface *(*instantiate)() = NULL;
  47
  48         *(void **)(&instantiate) = dlsym(m_marshallerHandle, "AM_InstantiateMarshaller");
  49
  50         if(instantiate == NULL) {
  51                 /* This is an error. */
  52                 std::cout << "Module exists, but does not have exported AM_InstantiateMarshaller() . . ." << std::endl;
  53                 std::cout << "\tDid you forget to place it in an extern \"C\" block?" << std::endl;
  54         }
  55         else {
  56                 m_instance = instantiate();
  57         }
  58 }
  59
  60 void Module::loadPreprocessor() {
  61         std::string ppPath = Coordinator::instance()->vault()->get(m_moduleName + ":preprocessorPath");
  62         if(ppPath == "") return;
  63         std::string path =
  64                 Coordinator::instance()->vault()->get(m_moduleName + ":root") + ppPath;
  65
  66         m_preprocessorHandle = dlopen(path.c_str(), RTLD_LOCAL | RTLD_NOW);
  67         if(m_preprocessorHandle == NULL) return;
  68
  69         Common::Preprocessor preprocessor;
  70
  71         *(void **)(&preprocessor) = dlsym(m_marshallerHandle, "AM_Preprocess");
  72
  73         if(preprocessor == NULL) {
  74                 /* This is an error. */
  75                 std::cout << "Module exists, but does not have AM_Preprocess() . . ." << std::endl;
  76         }
  77         else {
  78                 preprocessor(Coordinator::instance()->vault());
  79         }
  80 }
  81
  82 } // namespace Module
  83 } // namespace Monitor